Vaccination for Patients With Immunosuppression and Altered Immunity: A Workgroup Report from the AAAAI Adverse Reactions to Drugs, Biologics, and Vaccines Committee and the Autoimmunity and Altered Immune Response Committee.

Vaccination, a fundamental strategy for infectious disease prevention, presents unique challenges in individuals with altered immunity. These populations include individuals with inborn errors of immunity, autoimmune and inflammatory diseases, solid organ transplants, hematopoietic stem cell transplants, biologic and immunosuppressive therapies, and pregnancy. Despite concerns regarding variable vaccine responses, altered efficacy, and safety profiles, these groups remain under-represented in clinical trials. This review synthesizes current evidence on immunization outcomes in medically complex populations, highlighting strengths and limitations in existing research. We describe how altered immunity affects vaccine responses, summarize data on adverse reactions, and examine the influence of biologic therapies and pregnancy. Our analysis identifies significant gaps, including insufficient long-term durability data, inadequate safety surveillance for special populations, and limited incorporation of precision medicine approaches. We propose recommendations to address these deficiencies, including targeted vaccine trials for special populations, broader trial inclusion, enhanced outcome measures, refined safety monitoring, and tailored vaccine guidance. By advancing precision immunization strategies, clinicians and researchers can optimize vaccine protection for vulnerable groups, promoting equitable access and improving public health outcomes.